There's really no perfect answer to either question I'm afraid.
You'll find it difficult to sell a html5 game outright, as anybody can access the game once its on the net. You can do a few things like unlock certain parts when a user buys access using a code, or perhaps place the game on a page with adds.
Then there is no time frame for an exe, or even a guarantee that there will be one. All we know right now is an exporter will be possible when a development kit is released sometime in the future.